The Green Bank Observatory is located in the beautiful mountains of West
Virginia.
We use radio telescopes to study the properties
of giant molecular clouds in our galaxy, which are the sites of star formation.
We also are part of a world wide Very Long Baseline Interferometry
(VLBI) network that is used to study the physics of black holes
at the center of active galaxies and quasars.

The whole sky is shown above, with the Galactic Plane A survey shown
in color. The Galactic Center, Cygnus Region and Rosette Nebula are
emphasized. Follow the link to
select
a region.

Research

HVCs and Galaxy Groups
Chynoweth, Langston and collaborators have used the GBT
to discover new neutral hydrogen components of the M81/M82
group of galaxies. These clouds are thought to be analogs of the
high velocity clouds (HVCs) surrounding our own galaxy.

GBT Chemistry
The GBT Astro-chemistry observations have been very successful.

The MIT-Lincoln Laboratory-NRAO collaboration uses 43m telescope
for bistatic radar observations of spacecraft in order to study
properties of the Earths' Ionosphere.

Mathematica Free Fall Doppler Calculations

A series of Mathematica calculations are
presented outline the steps toward calculating the observations
of a freely falling observer, as the approach a black hole.
The
first case
considered is the free fall time from the Earth (1 AU) to the
Sun.
FYI the simple classical calculation yields a time of 64.6 days.
The results are available in a Mathematica
Notebook and a PDF.

Orbiting Very Long Baseline Interferometer

The
Orbiting VLBI
tracking station in
Green Bank,
West Virginia is one of four NASA tracking stations dedicated to
support of the space vlbi missions in Japan and Russia.
The HALCA satellite is used to study the properties of
jets of material ejected from the region surrounding
black holes at the centers of distant galaxies.

Monitoring Our Galaxy

The NRAO/NASA tracking station is being used to monitor the
Milky Way Galaxy for transient radio sources.
The first galactic plane survey at 8.35 and 14.35 GHz is
available.

In the movie to the right, the Cygnus X-3 (a binary star
system in our galaxy) exhibited transient emission on 2000 April 20.
The binary stars appear as a red peak in the center of one of the images.
The radio emission of this region is compared to the Galactic Plane
The GPA 8.4 GHz Survey image taken on 1998 September.
The brightest emission is in red and faintest emission is in blue.
The GP 8.4 image was taken on 2000 April 20 and has
a higher noise level than the GPA image. The green emission differences
are not significant. The ROSAT images shows the bright xray source.
The Optical Digitized Sky Survey image (CYGNUS X-3) shows no significant
emission because the system is imbedded in a dark cloud of gas.

Gravitational Lens MIT Green Bank 1654+1346

The MIT Green Bank survey of the sky at 5 GHz detected a
number of gravitational lenses including the MG 1654+1345 system.
In this system, a distant radio bright quasar is gravitational lensed
by a closer foreground galaxy. This system was the first in which the mass
of the lensing galaxy could be deduced based on the size of the lens
image and the redshifts of the galaxy and quasar.

Green Bank hosted the
High Redshift Radio Lines
workshop. The proceedings are available from the P.A.S.P.,
edited by C. Carilli, K. Menton, S. Radford and G. Langston.

High Redshift Absorption Lines

Keri Eberhardt, Robert Brown and I observed a sample of high
redshift (3.35 < z < 3.83) radio bright quasars, searching for
HCN and CO absorption lines. This observations have yielded
no detections, and we place limits on the column density of cold
gas at high redshift.

Publications

An index
of my publications is available, many with postscript copies
available online.

The 140ft telescope has contributed to the discovered interstellar chemistry!
Many molecules have been first detected in interstellar space using
the 140ft telescope.
The chemical structure of these molecules is shown.

The NRAO solar system
tour
guide map is presented in a variety
of forms. A scale model solar system has been set up on the NRAO
site (scale 1:3,000,000,000). The locations and relative size
of the sun and planets are shown.